This application requests funding for 4 postdoctoral fellows to be trained in research relating to the development of vaccines. Training will emphasize principles crucial for design of vaccines for prevention of infectious diseases, treatment of cancer and autoimmunity and prevention of unwanted immunity in gene therapy. The major emphasis of training will be on laboratory work under the supervision of one of the trainers. This training will be supplemented with a bench course in techniques relevant for state of the art vaccine development, a didactic course on novel types of vaccines and clinical vaccine development, a course in proper scientific conduct, discussion groups and seminars. The training faculty is composed of a total of 19 primary trainers (including the Program Director), 12 from The Wistar Institute, 3 from The Children's Hospital of Philadelphia, and 2 from the University of Pennsylvania School of Veterinary Medicine and 2 from the University of Pennsylvania Medical School. The trainers are from diversified backgrounds such as cellular immunology, autoimmunity, parasitology, virology, viral immunology, molecular biology, structural biology and gene therapy with a shared interest in vaccine development thus offering a multidisciplinary approach that is focused on the immunobiology of vaccines. Collaborations between the trainers are ongoing and will encompass the trainees supported by this application. Training will be coordinated by a Training Committee composed of the Program Director and 4 of the primary trainers. This committee will also select the candidates to be sponsored by this program giving special attention to the recruitment of trainees from underrepresented minority groups. The candidates admitted to the program will initially be accepted for one year. Upon evaluation the training period can be extended for up to three years. Laboratory training will take place in the facilities of the primary trainer either at The Wistar Institute, The University pf Pennsylvania, The Children's Hospital of Philadelphia, or The University of Pennsylvania School of Veterinary Medicine which are all located on the same street within two blocks from each other. All of the course work will take place at The Wistar Institute.